In such vehicles it has already been suggested to power the two traction wheels via a differential gearing, enclosed in an axle housing, from a preferably hydrostatic drive motor carried on that axle housing so as not to encumber other parts of the vehicular frame which must accommodate, in the case of a fork-lift truck, the lifting mechanism as well as a driver's seat in addition to the load. In such prior constructions, however, it was generally necessary to mount the drive motor well above the transverse horizontal axis of the traction wheels in order to find room within the housing for various transmission elements such as speed-reducing planetary-gear trains. The considerable distance of the motor shaft from the wheel axis required the insertion of additional gears between a pinion on the drive shaft of the motor and a driven element in the axle housing, such as a toothed ring of a differential-gear housing.